1. Field of the Invention
The present invention relates to a positioning structure of a bearing and an axle tube, and more particularly to a positioning structure of a bearing and an axle tube, which can prevent the center of the bearing from deflecting efficiently, enhance the lubricating effect, and can save the cost of fabrication.
2. Description of the Related Art
In general, when a conventional bearing is mounted in an axle tube, the inner wall of the bearing is formed with an oil storage groove or oil channel, for achieving the better oil storage and oil guide effects. A conventional positioning structure of a bearing and an axle tube in accordance with the prior art is shown in FIG. 1, wherein the inner wall of the bearing 1 is formed with an oil storage groove 10 for providing a lubricating effect during rotation of the rotation shaft 12. By formation of the oil storage groove 10, the excessive lubricating oil released from the bearing 1 may be stored in the oil storage groove 10 temporarily without being leaked outward, thereby increasing the lifetime of the bearing 1. At the same time, the friction area between the bearing 1 and the rotation shaft 12 is reduced, thereby decreasing the friction force therebetween, so that rotation of the rotation shaft 12 is more convenient. However, the conventional positioning structure of the bearing 1 and the axle tube 14 has the following disadvantages:
1. The center of the bearing is easily deflected:
The conventional bearing 1 is directly pressed into the positioning hole 140 of the axle tube 14 in a tight fit manner. Thus, the periphery of the bearing 1 is deformed by the frictional squeeze of the inner wall of the positioning hole 140 of the axle tube 14, so that the center of the shaft hole 16 of the bearing 1 is easily deflected. Thus, the rotation of the rotation shaft 12 in the shaft hole 16 is inconvenient, thereby easily producing noise.
2. The cost of fabrication is high:
The conventional bearing 1 is directly formed with the oil storage groove 10 in the inner wall of the shaft hole 16. Therefor, the bearing 1 cannot be integrally formed with the oil storage groove 10 during the molding process of the bearing 1, and the oil storage groove 10 needs to be formed by a working process additionally, thereby causing inconvenience in fabrication and thereby increasing the cost of fabrication.
The primary objective of the present invention is to provide a positioning structure of a bearing and an axle tube, which can prevent the center of the bearing from deflecting efficiently, can enhance the lubricating effect, and can save the cost of fabrication.
Accordingly, the main feature of the present invention is in that the positioning hole of the axle tube has a periphery formed with an oil storage space corresponding to the bearing, so that when the bearing is received and positioned in the positioning hole of the axle tube, the friction force between the bearing and the inner wall of the positioning hole can be reduced efficiently. Thus, the shaft hole of the bearing is not easily deformed due to squeeze, thereby preventing the center from deflecting. At the same time, the oil storage space is relatively increased, thereby enhancing the lubricating effect of the bearing. The oil storage space is directly integrally formed in the periphery of the positioning hole during fabrication of the shaft tube. Thus, the fabrication is rapid, thereby decreasing the cost of fabrication.
Further benefits and advantages of the present invention will become apparent after a careful reading of the detailed description with appropriate reference to the accompanying drawings.